1. Field of the Invention
This invention relates to the chemical arts. In particular, it relates to a culture medium and a cultured milk used to make no fat or low fat cheese products and to a method for making such cheese products.
2. Discussion of the Related Art
In recent years, for health as well as cosmetic reasons, there has developed an increasing concern with diet which has focused on reduced fat consumption. Low fat foods which look and taste like their higher fat counterparts have been eagerly sought by the public. To this end, food researchers have concentrated on developing food products which are nutritious and palatable, but which contain substantially reduced levels of fat. This is particularly true in the dairy industry where such reduced fat products as skim milk and yogurt have been successfully marketed. However, the successes in these areas have not carried over to methods for preparing no fat or low fat cheeses having high consumer acceptance.
Attempts have been made to use skim or low fat milk in conventional cheese making processes, to produce no fat or low fat cheeses. Unfortunately, the body, texture and flavor of the resulting no fat or low fat cheese products have not been entirely satisfactory for ordinary consumer use. The cheeses tend to be extremely hard, leathery and tough, and are often almost completely devoid of flavor. Therefore, it is a desideratum for a process which results in the preparation of no fat or low fat cheese products having similar body, texture and flavor when compared to their full fat counterparts.
Typically, in the manufacture of no fat or low fat cheese, raw or pasteurized skim or low fat milk is placed in a vat and heated to an appropriate temperature. Bacteria, such as S. cremoris, S. lactis, S. citrovorous, S. thermophillus, L. bulgaricus, L. casei and L. heleveticus, are approved lactic acid- and hetero-acid-producing cultures that when added to the milk begin to produce lactic acid and other products, such as fatty acids, butyrates and octanoates, which effect the body, texture and flavor of the final cheese product. To aid in their production, the acid bacteria are often combined with a culture medium before addition to the milk.
After addition of the bacteria, the milk is allowed to ripen until a desired degree of acid has been produced. The milk at this stage is known as cultured milk. Rennet is added to the cultured milk to form a coagulum. When the coagulum has reached a desired degree of firmness, it is cut to form curd in a whey solution. The vat is then heated to between about 95.degree. F. and 120.degree. F. and held at a temperature in this range for a period of time sufficient to cook the curd, causing the curd to continue firming and the bacteria to continue producing lactic acid and other products which effect the body, texture and flavor of the final cheese product. The whey solution is then drained leaving a firm, resilient curd. The disposal of whey can be a problem and it is desirable to be able to recycle the whey to the greatest possible extent. Consequently, it is also a desideratum to maximize the amount of recyclable whey that can be recovered from a no fat or low fat cheese making process.
After the vat is drained of the whey solution, the curd is salted. In certain conventional processes, salting cannot occur until after bacteria have produced sufficient acid to cause the curd to have a pH of less than 5.5. The addition of salt has the affect, inter alia, of significantly decreasing the bacterial activity, thereby lessening production of additional lactic acid and other products. After salting, the cheese is typically further processed, such as by aging which allows additional development of lactic acid and other byproducts effecting the final body, texture and flavor of the desired cheese product. Because the salting step slows down the production of lactic acid and other products, aging can be a time-consuming process requiring from several weeks to several years.
It can be appreciated from the above description that the cheese making process is time-consuming, particularly because of the time required for the pH and flavor of the curd to develop before salting and because of the time required to ripen the cheese after it has been salted. Therefore, it is also a desideratum to minimize the time required to manufacture no fat or low fat cheese with desirable attributes and thereby increase the efficiency of the cheese making process.
Accordingly, there has existed a definite need for an improved method for preparing no fat and low fat cheese products having a more similar body, texture and flavor when compared to their full fat counterparts. There has existed a still further need for an improved method for preparing no fat or low fat cheese products minimizing the time required to produce a final cheese product, while maximizing the amount of recyclable whey. The present invention satisfies these and other needs and provides further related advantages.